Don't update system table for unknown nodes/dead states
Patch by Tyler Hobbs, reviewed by brandonwilliams for CASSANDRA-6053
Merge branch 'cassandra-1.2' into cassandra-2.0
Don't update system table for unknown nodes/dead states
Patch by Tyler Hobbs, reviewed by brandonwilliams for CASSANDRA-6053
make isDeadState public
Merge branch 'cassandra-1.2' into cassandra-2.0